A thin-film transistor (TFT) on an array substrate comprises structures such as a source, a drain and a gate, wherein the source or the drain is connected with a data line. Data lines on the array substrate are long and thin, and hence would break easily. As a result, the array substrate cannot operate normally.
In the related art, there is a method for manufacturing an array substrate. In this method, a transparent conductive layer is formed first on a base substrate, and after that, a pixel electrode and a second data line are formed on the transparent conductive layer by a patterning process. Then, a source, a drain and a first data line are formed by a patterning process on the base substrate on which the pixel electrode and the second data line have been formed, wherein the second data line has a same shape as the first data line. In this case, the first data line is superimposed on the second data line, which has a same shape as the first data line. The second data line is used for reducing possible breakage of the first data line. Even if the first data line breaks, the second data line under that breakage will connect the data line at the breakage.
As has been found by the inventor, existing approaches such as the one indicated above at least contains the following defects: due to factors such as human errors or mechanical errors, the first data line may fail to be superimposed on the second data line, which results in invalidation of the second data line.